Sheet metal burner and cross lighter



March 3, 1959 w. ALLEN swam METAL BURNER AND CROSS LIGHTER 2Sheets-Sheet 1 Filed Nov. 9, 1954 Ma. rh 3, 1959' a. w. ALLEN SHEETMETAL BURNER AND CROSS LIGHTER 2 Sheets-Sheet 2 Filed NOV. 9, 1954United States Patent O SHEET METAL BURNER AND CROSS LIGHTER George W.Allen, Indianapolis, Ind., assignor to Stewart- Warner Corporation,Chicago, Ill., a corporation of Virginia Application November 9, 1954,Serial No. 467,731

3 Claims. (-Cl. 158115) The present invention relates to gas burnersadapted to be mounted alongside each other.

One object of the invention is to provide an improved gas burner adaptedto be used alongside similar burners and having highly efficient meansfor vcross lighting between burners.

A further and more specific object is to provide an improved gas burnerof the above character which is well suited for economical fabricationfrom sheet metal.

Other objects and advantages will become apparent from the followingdescription of the form of the invention illustrated in the drawings, inwhich:

Figure 1 is a plan view of a burner embodying the invention;

'Fig. 2 is a side view of the burner of Fig. 1;

Fig. 3 is a right end view of two burners mounted side by side;

Fig. 4 is a fragmentary plan view on an enlarged scale of onecross-lighting runner; and

Fig. 5 is a fragmentary vertical view on an enlarged scale of across-lighting runner as viewed from the outer end.

The gas burner incorporating the invention is adapted to be mounted sideby side with similar burners, Fig. 3, in a heater or furnace (not shown)to providethe heating capacity desired. Each burner is symmetrical abouta vertical longitudinal plane and is relatively narrow in relation toits length.

A long narrow series of burner openings extending along the top of theburner, Figs. 1 and 2, are fed with a mixture of gas and air from ahorizontally elongated plenum chamber 12 underlying the openings. Theplenum chamber 12 is widened generally from top to bottom and deepenedfrom its outer ends toward the center. The lower central portion of thechamber merges with the upper end of a short vertical passageway 14connected with the inner end of a horizontal fuel mixing tube 16. Shapedand dimensioned in accordance with conven-.

tional burner design practice, the mixing tube 16 has a circulartransverse configuration which sharply decreases in diameter from theouter end 20 of the tube to a venturi throat 18 and then progressivelyincreases in diameter to the inner end of the tube which merges with thepassageway 14.

The mixing tube 16, the plenum chamber 12 and the connecting passageway14 are fashioned in a very economical manner from two generally verticalsheet metal plates 22, 24 formed substantially as mirror images of eachother. Both plates are blanked to have a generally rectangular shape,the upper right and the lower left corners of each plate being cut away,as shown in Fig. 2.

Each plate 22, 24 is shaped by suitable dies or the like to form anelongated bulge 26 therein extending horizontally inward from the lowerright corner of the plate, Fig. 2, in spaced relation to the lowermarginal edge of the plate. Each bulge 26 is displaced away from theopposed plate and shaped to form a one-half section of the mixing tube16. The inner end of the bulge 26 in each 2,375,821 Patented Mar. 3,1959 ice plate merges with an upwardly extending bulge 28 shaped toform' a half section of the passageway 14; The upper end of the bulge 28merges with a much larger bulge 30, which fans out horizontally in bothdirections and extends to the upper edge of the plate to'forrn a halfsection of the plenum chamber 12. The upper edge of each plate 22, 24extends horizontally a short distance beyond the opposite extremes ofthe plenum chamber bulge 30 in theplate. v

The two plates 22, 24 are fastened in face .to face engagement bysuitable spot and seam welds 32 and 34 forming gastight seals betweenthe plates running along opposite sides of the mixing tube 16, thepassageway 14, and the plenum chamber 12. I

As shown in Figs. 1 and 2, the uppermarginal edge of each plate 22, 24above the plenum chamber bulge 30 in the plate is olfset horizontallyoutward from the opposite plate to form one straight vertical side 38 ofa long narrow burner opening channel 40. The extreme upper edges of theflat channel sides 38 are curled outwardly and downwardly to formreinforcing beads 41.

The flat channel sides 38 are positively held in spaced relation to eachother by four transverse members 44 spaced horizontally along thechannel 40 just below the channel sides and attached at opposite ends tofour I downwardly extending flats 46 on each plate 22, 24.

' burners, Fig. 3.

vertically disposed sheet metal stampings 58, 60 shaped The members 44also support a plurality of vertically corrugated ribbons 49 fittedinto. the channel 40 with flat spacer ribbons 50 between each corrugatedribbon to form the burner openings 10. The ribbons 49 and 50 are securedin place by two transverse clips 51 snapped over the beads 41 atopposite ends of the channel 40.

Short opposed end sections 52 of the plenum chamber bulges 30 at themixing tube end of the channel 40 are flattened to extend straight downfrom the flat channel sides 38. A central aperture 54 is formed in eachend flat 52. p

The apertured flats 52 form support bases for horizontally elongatedcantilever lighters or runners 56 brazed to the flats and projectinglaterally toward adjacent Each runner 56 is formed from two as mirrorimages of each other, except for certain structural features to bepresently described. Each stamping has a generally flat marginal edge 62of U-shape configuration extending around the stamping from points onthe adjacent flat 52 above and below the aperture 54 in the flat. Acentral, horizontally elongated bulge 64 in each stamping 58, 60 isoffset outwardly from the opposed stamping and extends from the adjacentsupport flat 52 to the U-shaped marginal edge 62 of the stamping. Thebulges 64 in the two stampings of each runner 56 form a passagewaywithin the runner which communicates with the interior of the plenumchamber 12 through the adjacent aperture-54, which is almost entirelyencircled by the runner.

The upper edges of the runners 56 adjacent the plenum chamber 12 aresubstantially flush with the upper edges of the burner ribbons 49, 50.'Outwardly from the plenum chamber 12, the upper edge of each runner 56curves downwardly with a progressively increasing curvature to theextreme end of the runner.

The lower portions 65 of the opposed marginal edges 62 of the twostampings'SS, 60 of each runner 56are seam welded together up to ahorizontal offset line 66' (see Figs. 3 to 5) extending through theextreme outer stream of fuel mixture extending from the burner openingsto the outer end of the runner from which the fuel mixture is directedhorizontally (just above the offset line 66) toward a similar runner onthe adjacent burner (see Fig. 3). Inthis' manner the runners 56 ofadjacent burnersprovide a substantially continuous stream of fuelmixture extending" from burner to burner for efficient, dependablecross-lighting between burners.

To provide further assurance of unfailing cross lighting between burnerswhen the gas pressure is extremely low, an auxiliary channel 71 isswaged rearwardly in the upper marginal edge 62 of the rear stamping 60of each cross lighter 56 to extend outwardly at a somewhat upwardlyinclined angle from the outer end of the central bulge 64 in thestamping to the extreme outer edge of the lighter gap 70. The crosslighter channels 71 increase the flow of gas horizontally from thelighters of adjacent burners as a further aid to the progress of flamefrom lighter to lighter.

In the event that the gas outlet gap 70 of one or more of the burnercross lighters 56 should become blocked by falling scale or otherwise (amost unlikely condition) effective cross lighting between burners iseffected by gas supplied through a row of auxiliary lightin'g ports 73drilled in the front stamping 58 of each lighter 56 and extendinggenerally from the outer end of the lighter to the plenum chamber 12.

Fuel gas is supplied to each burner through a conventional nozzle (notshown) fitted into a support 72 extending across the outer end of themixing tube 16.

'Formed almost entirely of sheet metal, the improved burner is,extremely economical to manufacture. The

[sheet metal construction is inherently resistant to breakage. Moreover,the two plates 22, 24 form strong reinforcing webs 74, 76 betweenopposite ends of the plenum chamber 12 and the mixing tube 16 (Fig. 2).These webs can be used in mounting the burner.

While I have shown and described a preferred embodiinerit ofmyinve'ntion, it will be apparent that varia- -tions and modificationsthereof may be made without departing from the principles and scope ofthe invention as set out in the following claims.

I claim:

1. A sheet metal gas burner adapted to be used alongside another burnerand comprising, in combination, twoopposed generally vertical plates ofsheet metal formed substantially as mirror images of. each other, eachplate having an elongated bulge therein displaced outwardly from theopposed plate and shaped to form a half section of a fuel mixing tube,said mixing tube bulge of each plate merging with an enlarged bulgereaching to the upper edge of the plate and shaped to form a halfsection of a. plenum chamber, a large section of the upper marginal edgeof each plate being offset from theopposed marginal edge of the oppositeplate, said .plates b'eing welded in face to face engagement with eachother, means coacting with-said oflEset marginal edges of the two platesto define burner outlets from the space-betweensaid plenum chamberbulges of the 'two plates, the plenum chamber bulge of at least one ofsaid plates defining an aperture therein, a cantilever lighterof sheetmetal attached at one end to said one plate in embracing relation tosaid aperture therein, said lighter comprising two sheet metal stampingsattached respectively at one end to said one plate on opposite sides ofsaid (aperture therein, each stamping having a U-shaped marginal edgebounding the stamping generally in a substantially vertical plane as thestamping projects away from the adjoining plate, the central portion ofat least one stamping extending from the end thereof adjacentsaidaperture to said U-shaped marginal edge of the stamping beingbentoutwardly from the opposed portion of the other stamping to formtherewith an internal'lighter cavity communicating through said aperturewith the plenum chamber, that part of the one stamping central portionwhich delimits the upper extremity of the cavity turning outwardly fromthe plenum chamber and downwardly at a progressively increasing slope,the opposed portions of the U-shaped marginal edges of the two stampingsextending from the adjoined plate along the underside of the lighter tothe projecting end thereof and up to a generally horizontal line runningthrough the projecting end of the lighter being sealed together, theupper portions of said marginal edges of the two stampings above saidline curving outwardly from said adjoined plate and downwardly to theprojecting end of the lighter with a progressively increasing slope,said upper portions of said marginal edges of the two stampings abovethe line being offset horizontally from each other down to the line todefine a thin crosslighting fuel gap communicating with said internallighter cavity and opening upwardly and horizontally outwardly therefromto issue fuel from said cavity upwardly from the lighter andhorizontally outward from the projecting end thereof, a portion of saidmarginal edge of at least one of said lighter stampings disposed at theprojecting end of the lighter above said line being swaged away from theopposing portion of the marginal edge of the other stamping to have aspacing therefrom greater than the width of said cross-lighting gap toprovide for an increased flow of fuel from said internal lighter cavityhorizontally outward from the projecting end of said lighter, and one ofsaid stampings defining a plurality of auxiliary gas outlet aperturestherein communicating withsaid internal lighter cavity and disposedadjacent its upper marginal edge in a series extending substantiallyfrom said plenum chamber means to the projecting ,end of said lighter.

'2. In a combination heater construction of the type in which aplurality of gas burners are disposed adjacent each other and in which amixing tube integral with each of the burners causes air and gas to bemixed in. proper proportions and to be directed to a plenum chambermeans from which the gas is emitted through burner ports for ignition,the combination with each of the burners of a cross lighter constructionwhich permits limited variable spacing and misalignment between theburners comprising a pair of sheet metal stampings in engagement witheach other, fixed at one end of the respective plenum chamber means, andextending toward an adjacent burner, the central portion of at least onestamping being bent outwardly from the opposed portion of the otherstamping to form therewith an internal cavity in the lighter, that partof said central portion which delimits the upper extremity of the cavityextending outwardly from the plenum chamber means and downwardly at aprogressively increasing slope, passageway means connecting the cavitywith the plenum chamber, the lower edges of the two stampingsbeingsealed together from the plenum chamber means toa'Qcentral.generally horizontal linerin their outer ends, the tuppernmarginal:edges of the two stampings turning outwardly from said plenum chamberand downwardly toward the projecting end of the lighter to said line ata progressively increasing slope, said upper edges being narrowly spacedfrom each other to define a thin cross lighting fuel gap communicatingwith the lighter cavity and opening upwardly and horizontally outwardlythere from to issue ,fuel from said cavity upwardly from the lighter andhorizontally outwardly from the projecting endthereof, and one .of saidstampings defining adjacent its-upper edge a plurality of auxiliary gasoutlet apertures arranged in a seriesextending substantially from said,plenumphamber means to the horizontal line.

3. In a combustion heater construction of the type in which a pluralityof gas burners are disposed adjacent each other'andin which a mixingtube integral with each of the burners causes air and gas to be mixed inproperproportions and, to be directed to a plenum burner ports forignition, the combination with each of the burners of a cross lighterconstruction which permits limited variable spacing and misalignmentbetween the burners comprising a pair of sheet metal stampings inengagement with each other, fixed at one end of the respective plenumchamber means, and extending toward an adjacent burner, the centralportion of at least one stamping being bent outwardly from the opposedportion of the other stamping to form therewith an internal cavity inthe lighter, that part of said central portion which delimits the upperextremity of the cavity extending outwardly from the plenum chambermeans and downwardly at a progressively increasing slope, passagewaymeans connecting the cavity with the plenum chamber, the lower edges ofthe two stampings being sealed together from the plenum chamber means toa central generally horizontal line in their outer ends, the uppermarginal edges of the .two stampings turning outwardly from said plenumchamber and downwardly toward the projecting end of the lighter to saidline at a progressively increasing slope, said upper edges beingnarrowly spaced from each other to define a thin cross lighting fuel gapcommunicating with the lighter cavity and opening upwardly andhorizontally outwardly therefrom to issue fuel from said cavity upwardlyfrom the lighter and horizontally outwardly from the projecting endthereof, and the edge of at least one of the stampings being bentoutwardly from the opposed portion of the other stamping adjacent thehorizontal line to define an auxiliary gas outlet channel communicatingwith the cavity and inclined upwardly and outwardly toward an adjacentburner.

References Cited in the file of this patent UNITED STATES PATENTS709,356 Piper Sept. 16, 1902 1,161,438 Bell Nov. 23, 1915 1,289,555Schall et a1. Dec. 31, 1918 2,470,880 Zimbelman et a1. May 24, 19492,541,428 Leo et al Feb. 13, 1951 2,560,777 Reeves July 17, 19512,658,504 Jaye et al. Nov. 10, 1953 2,658,569 Hughes et al Nov. 10, 1953

